This invention relates to a method of making a cutting member by assembling together a cutter body and an elongated shank, as well as to the cutting member made according to the method.
Cutting members of the type to which the invention is directed, adaptable for manual or machine operation, include a cutter body having serrations or cutting edges thereon, and an elongated shank capable of being clamped into a chuck of a machine to facilitate, for example, a drilling operation.
Some known cutters, especially of the small variety, are of one-piece construction such that the cutter body and shank are turned from solid stock material or, in the case of hard metal, are ground into shape.
On the other hand, prior cutting members of two-piece construction include a cutter body having a threaded recess for threaded engagement with the threads on one end of the shank. Otherwise, for a cutter body of hard metal, hard-solder is utilized for brazing the shank thereto.
The known cutter member assemblies of the aforedescribed type are not without their disadvantages. For example, the cutting member of one-piece construction requires a considerable amount of material, produces much waste and is expensive to machine. And, when subjecting this single-piece construction to heat treatment, a compromise must be reached between the different demands made on the cutter body (extreme hardness) and on the shank (high toughness).
The threaded together cutter body and shank has the particular disadvantage in that the interengaging threads must be precisely machined to assure a tight and secure fit between the cutter body and the shank thus increasing the time and expense of fabrication.
The principle disadvantage in using a hard-solder securement between the parts in that the shank surface sometimes undergoes quality changes at least in the brazing area and therefore has the tendency to break in such area.